1. Field
The following description relates to updating a sensor node included in a sensor network, and more particularly, to a sensor node included in a sensor network, an update server updating the sensor node, and a method of updating a sensor node.
2. Description of the Related Art
In general, a sensor network that connects sensor nodes installed in an environment involving the sensors in measurement is used to collect values measured by the sensors. Sensor networks are installed in various environments. Thus, an installation environment may be different from an environment for which the corresponding sensor network is originally designed, or a program installed in a sensor node may not match with an environment because the environment varies as time goes on. In this case, information collected by a sensor according to an unsuitable program for an actual environment may have low usefulness.
This problem can be solved by newly installing a suitable program for a current environment in a sensor node. However, it is difficult to install a new program in the already-installed sensor nodes one by one. To this end, a method of wirelessly installing the new program is needed. Since such a method uses limited wireless resources, it is necessary to transfer a new program to sensor nodes using as small amount of transmission as possible.
According to conventional art, a script-level change is made to update each sensor node with an appropriate execution code. Otherwise, execution codes for various uses are prepared for execution in each sensor node, and a server manages the execution codes and instructs appropriate execution.
Even if an execution code needs to be downloaded for an update, a sensor node downloads the entire execution code. While enabling execution of a desired program, such a method excessively uses limited network resources. Thus, the method puts a heavy load on an operating network and is difficult to use.